Chuck fixture for tube bending apparatus



06. 25, 1966 H. S CHMIDT CHUCK FIXTURE FOR TUBE BENDING APPARATUS Filed Nov. 27, 3

v 0 mm W T w NM EH WWW E I s W N A m .y w? E United States Patent 3,280,612 CHUCK FHXTURE FQR TUBE BENDING APPARATUS Hans Schmidt, Aurora, llL, assignor to Pines Engineering (10., Inc., Aurora, 151., a corporation of Illinois Filed Nov. 27, 1963, er. No. 326,578 2 Claims. (will. 72-298) This invention relates to improvements in tube bending apa'ratus and is particularly concerned with the novel construction of a chuck-fixture assembly designed to selectively clam rotate and advance a length of tubular stock or like article to the bending dies.

More particularly, the chuck is carried on a fixture that is slidable toward and away from the apparatus bending dies so as to permit progressive advance of the tubular stock through said dies for performing successive bends therein at the same or different radial angles. This is accomplished by mounting the chuck-fixture assembly on longitudinal guides and associating with it a screw that operates to advance and withdraw the assembly. The chuck is controlled by air pressure so as to automatically engaged with tubular stock of various diameters and is associated with drive means operable at selective intervals to rotate the tubular stock about its axis.

It is, therefore, an object of the invention to provide a chuck assembly of the character referred to.

Another object is to provide a novel structure and means for actuating a chuck.

Another object of the invention is to provide a chuck assembly of the character referred to which is not expensive to manufacture and is positive and efficient in its operation.

The structure by means of which the above noted and other objects and advantages of the invention are attained will be described in the following specification, taken in conjunction with the accompanying drawings, showing a preferred illustrative embodiment of the invention, in which:

FIG. 1 is a diametrical sectional view of the chuckfixture assembly, showing parts in elevation;

FIG. 2 is a view looking at the chuck end of the assembly, showing parts broken away; and,

PEG. 3 is a detail sectional View taken on line 3-3 of FIG. 2.

Referring to the accompanying drawings, the chuckfixture assembly comprises a substantially cylindrical housing 11 having at least one pair of downwardly extending outwardly diverging legs 12 each terminating in a cylindrical mounting boss 13, including bearing bus' ings 14. These mounting bosses are fitted over and are guided along a pair of rigid guides, such as rods 15, so that the assembly can be shifted longitudinally along said guides in either direction.

The housing 11 includes a cylindrical body portion 16 having an axially apertured wall 17 at one end and an axial neck 18 of reduced diameter extending outwardly from its other end, said neck terminating in an external flange 19 with which the legs 12 merge.

An axial sleeve 21 is mounted in the housing, suitable anti-friction bearings 22-23 being provided therefor in the end wall 17 and neck 18, respectively. The sleeve mounts firmly, intermediate its ends and Within cylindrical body 16, a ring gear 24 with which is meshed at all times a worm gear 25 mounted on a vertical shaft 26 depending from a motor 27. This gear-shaft assembly is enclosed in a casing 28 secured to one side of housing 11, as best shown in FIG. 3, and the motor 27 is secured firmly on the upper end of said casing. It should be evident that during operation of motor 27, which is a reversible type, the sleeve 21 may be rotated in either direction.

A chuck assembly, generally indicated at 29 is mounted firmly on the external neck flange 19. As best shown in FIG. 1, this assembly includes a back wall 31 that is secured to flange 19, as by bolts 32, and which has an internal annular [flange 33 mounting a sealing ring 34. A cylindrical wall 35 is secured to the outside margin of said back wall 31 to define a cylinder within which a ring type piston 3-6 may operate. This piston includes an inner flange 37, on which the sealing ring 34 seats, and its outer perimeter carries a sealing ring 38 that has a sliding fit within cylindrical wall 35. The piston includes an external neck 39 in which is seated the outer raceway of an antifr-iction bearing 41.

The forward end of axial sleeve 21 mounts firmly, as by set screws 42, a collet 43 having an outwardly flared external surface 44 over which is slidable a ring 45 upon which the inner raceway of bearing 41 is secured. A cap ring 46 closes the front end of the piston cylinder wall 35. The free end of the collet 43 mounts sizing segments 47 secured, as by screws 48, which are changeable for segments of different thicknesses to adapt the collet for holding tabular stock of different diameters. It should be obvious that when air is admitted under pressure into the interior of cylinder wall 35, as through a conduit 49, the piston 36 moves forward (to the right in FIG. 1) so as to contract the chuck firmly about a length of tubular stock 51. When pressure is relieved, the collet expands to release the tubular stock.

In order to advance the tubular stock towards and away from the bending dies, the housing 11 has a depending centrally located boss 52 carrying firmly an internally threaded body 53 through which a threaded rod 54 extends. This rod may have its forward end journalled for free rotation in a bearing block '55 mounted on a suitable support surface 56 and its other end is operably connected to a motor '(not shown) for selectively rotating said rod.

In operation, the assembly functions to grasp a length of tubular stock and feed it in successive stages to the bending dies. At predetermined times, determined by the setting of the controls for motor -27, the stock is rotated about its axis so as to position it in the dies for performance of a bending operation in a predetermined direction. In actual use, the operation of the chuck, drive motor for the threaded rod, and motor 27 are all controlled automatically so as to provide for a continous sequence of tubular stock feeding, rotating when required, and engagement and disengagement of the chuck with the stock at the start and finish of the bendin-g operations.

Although I have described a preferred embodiment of my invention, in considerable detail, it will be understood that the description thereof is intended to be illustrative, rather than restrictive, as many details of the structure disclosed may be modified or changed without departing from the spirit or scope of the invention. Accordingly, I do not desire to be restricted to the exact construction described.

What I claim and desire to secure by Letters Patent of the United States is:

1. In apparatus for performing work on a length of tubular stock, a non-rotatable housing, a sleeve extending through said housing and through which the stock extends, chuck jaws extending from one end of said sleeve and between which the stock extends, a collar surrounding said chuck jaws and movable axially thereover for contracting said jaws about the stock, a piston-cylinder assembly carried by said housing and having its piston operably associated with the collar for moving said collar in a direction to close the jaws, means operable to permit said jaws to open when the piston is ineffective,

and means in said housing to rotate the sleeve and chuck aws.

2. In apparatus for performing Work on a length of tubular stock, elongated guide rails, -a non-rotatable housing slidable along said guide rails, screw means operable to advance and retract the housing along said giude trails, a sleeve extending through said housing and through which the stock extends, chuck jaws extending from one end of said sleeve and between which the stock extends, a collar surrounding said chuck jaws and movable axially thereover for-contracting said jaws about the stock, -a piston-cylinder assembly carried by said housing and having its piston, operably associated with the collar for moving said collar in a direction to close 4 i when the piston is ineffective, and means in said housing to rotate the sleeve and chuck jaws.

References Cited by the Examiner UNITED STATES PATENTS 1,907,041 5/1933 Coe 72-307 2,306,223 12/ 1942 Parker et a1. 7222 2,312,121 2/1943 Parker et al. 72156 2,371,695 3/ 1945 Lancaster 72-156 3,145,756 8/ 1964 Hill 72298 3,177,688 4/1965 Kralowetz 72-311 CHARLES W. LANHAM, Primary Examiner.

the jaws, means operable to permit said jaws to open 15 L. A. LARSON, Assistant Examiner. 

1. IN APPARATUS FOR PERFORMING WORK ON A LENGTH OF TUBULAR STOCK, A NON-ROTATABLE HOUSING, A SLEEVE EXTENDING THROUGH SAID HOUSING AND THROUGH WHICH THE STOCK EXTENDS, CHUCK JAWS EXTENDING FROM ONE END OF SAID SLEEVE AND BETWEEN WHICH THE STOCK EXTENDS, A COLLAR SURROUNDING SAID CHUCK JAWS AND MOVABLE AXIALLY THEREOVER FOR CONTRACTING SAID JAWS ABOUT THE STOCK, A PISTON-CYLINDER ASSEMBLY CARRIED BY SAID HOUSING AND HAVING ITS PISTON OPERABLY ASSOCIATED WITH THE COLLAR FOR MOVING SAID COLLAR IN A DIRECTION TO CLOSE THE JAWS, MEANS OPERABLE TO PERMIT SAID JAWS TO OPEN WHEN THE PISTON IS INEFFECTIVE, AND MEANS IN SAID HOUSING TO ROTATE THE SLEEVE AND CHUCK JAWS. 